netconf/netconf-util/src/main/java/org/opendaylight/netconf/util/NetconfUtil.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.netconf.util;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11
  12 import com.google.common.collect.ImmutableMap;
  13 import java.io.IOException;
  14 import java.net.URISyntaxException;
  15 import java.util.Iterator;
  16 import java.util.List;
  17 import java.util.stream.Collectors;
  18 import javax.xml.stream.XMLOutputFactory;
  19 import javax.xml.stream.XMLStreamException;
  20 import javax.xml.stream.XMLStreamWriter;
  21 import javax.xml.transform.dom.DOMResult;
  22 import javax.xml.transform.dom.DOMSource;
  23 import org.eclipse.jdt.annotation.Nullable;
  24 import org.opendaylight.netconf.api.DocumentedException;
  25 import org.opendaylight.netconf.api.xml.XmlElement;
  26 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  27 import org.opendaylight.netconf.api.xml.XmlUtil;
  28 import org.opendaylight.yangtools.rcf8528.data.util.EmptyMountPointContext;
  29 import org.opendaylight.yangtools.rfc7952.data.api.NormalizedMetadata;
  30 import org.opendaylight.yangtools.rfc7952.data.util.NormalizedMetadataWriter;
  31 import org.opendaylight.yangtools.rfc8528.data.api.MountPointContext;
  32 import org.opendaylight.yangtools.yang.common.QName;
  33 import org.opendaylight.yangtools.yang.common.QNameModule;
  34 import org.opendaylight.yangtools.yang.common.Revision;
  35 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  36 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  37 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  38 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  39 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeWriter;
  40 import org.opendaylight.yangtools.yang.data.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  41 import org.opendaylight.yangtools.yang.data.codec.xml.XmlCodecFactory;
  42 import org.opendaylight.yangtools.yang.data.codec.xml.XmlParserStream;
  43 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNormalizedNodeStreamWriter;
  44 import org.opendaylight.yangtools.yang.data.impl.schema.NormalizedNodeResult;
  45 import org.opendaylight.yangtools.yang.model.api.ContainerSchemaNode;
  46 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  47 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  48 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  49 import org.slf4j.Logger;
  50 import org.slf4j.LoggerFactory;
  51 import org.w3c.dom.Document;
  52 import org.xml.sax.SAXException;
  53
  54 public final class NetconfUtil {
  55     /**
  56      * Shim interface to handle differences around namespace handling between various XMLStreamWriter implementations.
  57      * Specifically:
  58      * <ul>
  59      *   <li>OpenJDK DOM writer (com.sun.xml.internal.stream.writers.XMLDOMWriterImpl) throws
  60      *       UnsupportedOperationException from its setNamespaceContext() method</li>
  61      *   <li>Woodstox DOM writer (com.ctc.wstx.dom.WstxDOMWrappingWriter) works with namespace context, but treats
  62      *       setPrefix() calls as hints -- which are not discoverable.</li>
  63      * </ul>
  64      *
  65      * <p>
  66      * Due to this we perform a quick test for behavior and decide the appropriate strategy.
  67      */
  68     @FunctionalInterface
  69     private interface NamespaceSetter {
  70         void initializeNamespace(XMLStreamWriter writer) throws XMLStreamException;
  71
  72         static NamespaceSetter forFactory(final XMLOutputFactory xmlFactory) {
  73             final String netconfNamespace = NETCONF_QNAME.getNamespace().toString();
  74             final AnyXmlNamespaceContext namespaceContext = new AnyXmlNamespaceContext(ImmutableMap.of(
  75                 "op", netconfNamespace));
  76
  77             try {
  78                 final XMLStreamWriter testWriter = xmlFactory.createXMLStreamWriter(new DOMResult(
  79                     XmlUtil.newDocument()));
  80                 testWriter.setNamespaceContext(namespaceContext);
  81             } catch (final UnsupportedOperationException e) {
  82                 // This happens with JDK's DOM writer, which we may be using
  83                 LOG.warn("Unable to set namespace context, falling back to setPrefix()", e);
  84                 return writer -> writer.setPrefix("op", netconfNamespace);
  85             } catch (XMLStreamException e) {
  86                 throw new ExceptionInInitializerError(e);
  87             }
  88
  89             // Success, we can use setNamespaceContext()
  90             return writer -> writer.setNamespaceContext(namespaceContext);
  91         }
  92     }
  93
  94     private static final Logger LOG = LoggerFactory.getLogger(NetconfUtil.class);
  95
  96     // FIXME: document what exactly this QName means, as it is not referring to a tangible node nor the ietf-module.
  97     // FIXME: what is this contract saying?
  98     //        - is it saying all data is going to be interpreted with this root?
  99     //        - is this saying we are following a specific interface contract (i.e. do we have schema mounts?)
 100     //        - is it also inferring some abilities w.r.t. RFC8342?
 101     public static final QName NETCONF_QNAME = QName.create(QNameModule.create(SchemaContext.NAME.getNamespace(),
 102         Revision.of("2011-06-01")), "netconf").intern();
 103     // FIXME: is this the device-bound revision?
 104     public static final QName NETCONF_DATA_QNAME = QName.create(NETCONF_QNAME, "data").intern();
 105
 106     public static final XMLOutputFactory XML_FACTORY;
 107
 108     static {
 109         final XMLOutputFactory f = XMLOutputFactory.newFactory();
 110         // FIXME: not repairing namespaces is probably common, this should be availabe as common XML constant.
 111         f.setProperty(XMLOutputFactory.IS_REPAIRING_NAMESPACES, false);
 112         XML_FACTORY = f;
 113     }
 114
 115     private static final NamespaceSetter XML_NAMESPACE_SETTER = NamespaceSetter.forFactory(XML_FACTORY);
 116
 117     private NetconfUtil() {
 118         // No-op
 119     }
 120
 121     public static Document checkIsMessageOk(final Document response) throws DocumentedException {
 122         final XmlElement docElement = XmlElement.fromDomDocument(response);
 123         // FIXME: we should throw DocumentedException here
 124         checkState(XmlNetconfConstants.RPC_REPLY_KEY.equals(docElement.getName()));
 125         final XmlElement element = docElement.getOnlyChildElement();
 126         if (XmlNetconfConstants.OK.equals(element.getName())) {
 127             return response;
 128         }
 129
 130         LOG.warn("Can not load last configuration. Operation failed.");
 131         // FIXME: we should be throwing a DocumentedException here
 132         throw new IllegalStateException("Can not load last configuration. Operation failed: "
 133                 + XmlUtil.toString(response));
 134     }
 135
 136     @SuppressWarnings("checkstyle:IllegalCatch")
 137     public static void writeNormalizedNode(final NormalizedNode<?, ?> normalized, final DOMResult result,
 138                                            final SchemaPath schemaPath, final EffectiveModelContext context)
 139             throws IOException, XMLStreamException {
 140         final XMLStreamWriter writer = XML_FACTORY.createXMLStreamWriter(result);
 141         try (
 142              NormalizedNodeStreamWriter normalizedNodeStreamWriter =
 143                      XMLStreamNormalizedNodeStreamWriter.create(writer, context, schemaPath);
 144              NormalizedNodeWriter normalizedNodeWriter =
 145                      NormalizedNodeWriter.forStreamWriter(normalizedNodeStreamWriter)
 146         ) {
 147             normalizedNodeWriter.write(normalized);
 148             normalizedNodeWriter.flush();
 149         } finally {
 150             try {
 151                 if (writer != null) {
 152                     writer.close();
 153                 }
 154             } catch (final Exception e) {
 155                 LOG.warn("Unable to close resource properly", e);
 156             }
 157         }
 158     }
 159
 160     @SuppressWarnings("checkstyle:IllegalCatch")
 161     public static void writeNormalizedNode(final NormalizedNode<?, ?> normalized,
 162                                            final @Nullable NormalizedMetadata metadata,
 163                                            final DOMResult result, final SchemaPath schemaPath,
 164                                            final EffectiveModelContext context) throws IOException, XMLStreamException {
 165         if (metadata == null) {
 166             writeNormalizedNode(normalized, result, schemaPath, context);
 167             return;
 168         }
 169
 170         final XMLStreamWriter writer = XML_FACTORY.createXMLStreamWriter(result);
 171         XML_NAMESPACE_SETTER.initializeNamespace(writer);
 172         try (
 173              NormalizedNodeStreamWriter normalizedNodeStreamWriter =
 174                      XMLStreamNormalizedNodeStreamWriter.create(writer, context, schemaPath);
 175                 NormalizedMetadataWriter normalizedNodeWriter =
 176                      NormalizedMetadataWriter.forStreamWriter(normalizedNodeStreamWriter)
 177         ) {
 178             normalizedNodeWriter.write(normalized, metadata);
 179             normalizedNodeWriter.flush();
 180         } finally {
 181             try {
 182                 if (writer != null) {
 183                     writer.close();
 184                 }
 185             } catch (final Exception e) {
 186                 LOG.warn("Unable to close resource properly", e);
 187             }
 188         }
 189     }
 190
 191     /**
 192      * Writing subtree filter specified by {@link YangInstanceIdentifier} into {@link DOMResult}.
 193      *
 194      * @param query      path to the root node
 195      * @param result     DOM result holder
 196      * @param schemaPath schema path of the parent node
 197      * @param context    mountpoint schema context
 198      * @throws IOException        failed to write filter into {@link NormalizedNodeStreamWriter}
 199      * @throws XMLStreamException failed to serialize filter into XML document
 200      */
 201     public static void writeFilter(final YangInstanceIdentifier query, final DOMResult result,
 202             final SchemaPath schemaPath, final EffectiveModelContext context) throws IOException, XMLStreamException {
 203         if (query.isEmpty()) {
 204             // No query at all
 205             return;
 206         }
 207
 208         final XMLStreamWriter xmlWriter = XML_FACTORY.createXMLStreamWriter(result);
 209         try {
 210             try (NormalizedNodeStreamWriter writer =
 211                     XMLStreamNormalizedNodeStreamWriter.create(xmlWriter, context, schemaPath)) {
 212                 final Iterator<PathArgument> it = query.getPathArguments().iterator();
 213                 final PathArgument first = it.next();
 214                 StreamingContext.fromSchemaAndQNameChecked(context, first.getNodeType()).streamToWriter(writer, first,
 215                     it);
 216             }
 217         } finally {
 218             xmlWriter.close();
 219         }
 220     }
 221
 222     /**
 223      * Writing subtree filter specified by parent {@link YangInstanceIdentifier} and specific fields
 224      * into {@link DOMResult}. Field paths are relative to parent query path.
 225      *
 226      * @param query      path to the root node
 227      * @param result     DOM result holder
 228      * @param schemaPath schema path of the parent node
 229      * @param context    mountpoint schema context
 230      * @param fields     list of specific fields for which the filter should be created
 231      * @throws IOException        failed to write filter into {@link NormalizedNodeStreamWriter}
 232      * @throws XMLStreamException failed to serialize filter into XML document
 233      * @throws NullPointerException if any argument is null
 234      */
 235     public static void writeFilter(final YangInstanceIdentifier query, final DOMResult result,
 236                                    final SchemaPath schemaPath, final EffectiveModelContext context,
 237                                    final List<YangInstanceIdentifier> fields) throws IOException, XMLStreamException {
 238         if (query.isEmpty() || fields.isEmpty()) {
 239             // No query at all
 240             return;
 241         }
 242         final List<YangInstanceIdentifier> aggregatedFields = aggregateFields(fields);
 243         final PathNode rootNode = constructPathArgumentTree(query, aggregatedFields);
 244
 245         final XMLStreamWriter xmlWriter = XML_FACTORY.createXMLStreamWriter(result);
 246         try {
 247             try (NormalizedNodeStreamWriter writer = XMLStreamNormalizedNodeStreamWriter.create(
 248                     xmlWriter, context, schemaPath)) {
 249                 final PathArgument first = rootNode.element();
 250                 StreamingContext.fromSchemaAndQNameChecked(context, first.getNodeType())
 251                         .streamToWriter(writer, first, rootNode);
 252             }
 253         } finally {
 254             xmlWriter.close();
 255         }
 256     }
 257
 258     private static List<YangInstanceIdentifier> aggregateFields(final List<YangInstanceIdentifier> fields) {
 259         return fields.stream()
 260                 .filter(field -> fields.stream()
 261                         .filter(fieldYiid -> !field.equals(fieldYiid))
 262                         .noneMatch(fieldYiid -> fieldYiid.contains(field)))
 263                 .collect(Collectors.toList());
 264     }
 265
 266     private static PathNode constructPathArgumentTree(final YangInstanceIdentifier query,
 267                                                       final List<YangInstanceIdentifier> fields) {
 268         final Iterator<PathArgument> queryIterator = query.getPathArguments().iterator();
 269         final PathNode rootTreeNode = new PathNode(queryIterator.next());
 270
 271         PathNode queryTreeNode = rootTreeNode;
 272         while (queryIterator.hasNext()) {
 273             queryTreeNode = queryTreeNode.ensureChild(queryIterator.next());
 274         }
 275
 276         for (final YangInstanceIdentifier field : fields) {
 277             PathNode actualFieldTreeNode = queryTreeNode;
 278             for (final PathArgument fieldPathArg : field.getPathArguments()) {
 279                 actualFieldTreeNode = actualFieldTreeNode.ensureChild(fieldPathArg);
 280             }
 281         }
 282         return rootTreeNode;
 283     }
 284
 285     public static NormalizedNodeResult transformDOMSourceToNormalizedNode(final MountPointContext mountContext,
 286             final DOMSource value) throws XMLStreamException, URISyntaxException, IOException, SAXException {
 287         final NormalizedNodeResult resultHolder = new NormalizedNodeResult();
 288         final NormalizedNodeStreamWriter writer = ImmutableNormalizedNodeStreamWriter.from(resultHolder);
 289         final XmlCodecFactory codecs = XmlCodecFactory.create(mountContext);
 290
 291         // FIXME: we probably need to propagate MountPointContext here and not just the child nodes
 292         final ContainerSchemaNode dataRead = new NodeContainerProxy(NETCONF_DATA_QNAME,
 293             mountContext.getEffectiveModelContext().getChildNodes());
 294         try (XmlParserStream xmlParserStream = XmlParserStream.create(writer, codecs, dataRead)) {
 295             xmlParserStream.traverse(value);
 296         }
 297         return resultHolder;
 298     }
 299
 300
 301     // FIXME: document this interface contract. Does it support RFC8528/RFC8542? How?
 302     public static NormalizedNodeResult transformDOMSourceToNormalizedNode(final EffectiveModelContext schemaContext,
 303             final DOMSource value) throws XMLStreamException, URISyntaxException, IOException, SAXException {
 304         return transformDOMSourceToNormalizedNode(new EmptyMountPointContext(schemaContext), value);
 305     }
 306 }